Automatic smoke preventer



Feba 4, 1936 R, MILLE 2,030,017

AUTOMATIC SMOKE PREVENTER Filed sept. 26, 19:51 3 sheets-sheet 1 Feb. 4, 193,01.y R. MILL 2,030,017

AUTOMTIC SMOKE PREVENTER Filed Sept. 26, 1931- 3 Sheets-Sheet 2 Feb. 4,1936. R. MILLE 2,030,017

AUTOMATIC SMOKE PREVENTER Filed Sept. 26, 1931 5 Sheets-Sheet 5 Patented Feb. 4, 1936 UNITED STATES PATENT OFFICE Application September 26, 1931, Serial No. 565,356 In France September 26, 1930 3 Claims.

The present invention relates to an automatic smoke preventer and has for one of its main objects to provide a device ensuring complete combustion of smoke in reboxes, .and wherein,

for that purpose, a jet of live steam is brought to blow the heated air over the burning fuel with the elect that the carbon contained in the gases is completely oxidized.

It is also a 4desired feature of the invention toprovide an apparatus of the character mentioned having a member .adapted to operate the same automatically, at the right time and as long as necessary, and further having a silencer to assure quietness in operation.

Other important objects and advantages of the invention will be in part obvious and in part pointed out hereinafter.

In order that the invention and its mode of operation may be readily understood by those persons skilled in the art, I have in the accompanying drawings and in the detailed description based thereupon, set out a possible embodimentl of the saine.

In these drawings Fig. 1 is a front elevation of the furnace having my improved device mounted thereon,

Fig. 2 is a side elevation of the furnace door and the valve-operating means associated therewith.

Fig. 3 is a longitudinal section of the air ejector.

Fig. 4 is a cross section thereof taken on line 4-4 of Fig. 3.

Fig. 5 is a longitudinal section of the silencer.

Fig. 6 is an enlarged longitudinal cross section of the dashpot embodied in the invention.

Fig. 'l is a horizontal section on line 1-1 of Fig. 6; and

Fig. 8 is an enlarged detail of the members mounted at the lower end of the piston rod.

Referring more particularly to the drawings, wherein like characters of reference will designate corresponding parts throughout, it will appear from Figures 3 and 4, that the .air ejector embodied in my improved device comprises a body I internally screw-threaded as at 2 and provided with a connecting branch 3, likewise screw-threaded, which communicates with the interior of body I through an orifice 4. The body I presents an internal conical portion 5 and terminates with a beveled end portion 6. An air pipe 1 ts in the body I and is screw-threaded in order to receive a silencer which will be hereinaiter more speciiically described. The small end of the air pipe 1 is fitted in the conical portion 5 of body I with a clearance for the passage of steam, said clearance being adjusted by means of a lock nut 8. The steam enters through branch 3 .and sucks preheated air through pipe 1. Preheating of the air may be obtained by leading it through a properly constructed conduit in the -wall of the re box. Steam and air are mixed in chamber I0 and blown in the fire box through a tube II mounted for adjustment by means of screws I2 and lock nuts I3, screws I4 and lock nuts I5 being provided for locking the tube II in suitable positions. Combustion gases drawn out of the lire box are sucked in between body I and tube II.

The automatic control of steam delivery is assured by a dashpot comprising a cylinder I6 as shown in Figure 6, and closed at its upper end by means of a plug 56 provided with a head 56 in which is formed a circular opening 51 allowing the passage of a pin 58. This mode of assembly allows the plug 56 and the cylinder I6 to rock about the pin 58. The bottom of the cylinder forms a screw threaded bearing portion 59 wherein is fitted a. stufling box 60 held by a nut 6I secured upon the bearing portion 59. The piston rod 28 slides in the stufng box and carries a forkpiece 62. 'T'.he piston is mounted at the upper end of the rod 28 and is preferably constituted by a leather packing 21 interposed between the ring 63 which is pressed on its upper face by a washer 64 and by a nut 65 in screwthreaded engagement with the rod 28, and a second frustrum-shaped ring 66. The latter presses uporn a thin metal Washer 21 in which are provided radiating notches, thus forming spring blades forcing the packing against the inner wall of the cylinder. The rings 63 and 66, the packing 21 and the resilient washer 21 are perforated toprovide registering ports forming conduits 61. These conduits freely open into the apertures of the upper ring 63 and thus communicate with the cylinder. The lower end of conduits 61 are normally closed by a solid washer 68 pressed on the frustrum-shaped ring 66 by the action of a coil spring 69 encircling the rod 28 and having one end bearing on the washer 68 and the other end on a ring 10 secured by a pin 10 on the rod 28. A conduit 1I is provided throughout the lengthof the cylinder and ls closed at the upper extremity by a screw 12 which, at the same time, serves to secure thel plug 56 on the cylinder I6. The conduit 1I is bored adjacent the bottom thereof to provide a recess 1I of larger diameter wherein fits a stem 13 integral with a screw 14 secured in the bottom of the cylinder and terminating with a. needle valve 15 opposite the conduit 1i. Said conduit 1I communicates with the cylinder through an orifice 15 opening in the upper portion of the cylinder, and through a second orifice 11 opening in the lower portion of the cylinder, and in the annular recess 1l extending about the stem 13 of the screw 14. The orifices in the outer wall of the cylinder body opposite the orices 15 and 11 are closed by screw threaded plugs 11 which prevent any communication between the conduit and the exterior. Finally, the forkpiece 62, secured on the lower screw threaded end of the piston rod 28 carries a stud 18 on which are secured rings 19 pressing on each of the outer faces of the forkpiece 62 and two other rings 83 secured to each of the ends of the stud 18. A yoke 8l is fitted between the two free parts of the stud disposed between the rings 19 and 88; a bolt 82 on which are suitably engaged disks 33 acting as counter-weights, is attached to the yoke. These counter-weights exert om the piston rod 28, through the medium of the yoke 8l, of the forkpiece 82, a. pull the intensity of which is variable with the number of disks carried by the bolt 82.

A silencer is mounted on the inlet orice of` the air pipe 1 in the marmer represented in Figure 5. rThis silencer comprises a pair of frustrum-shaped parts 3l and 32 interconnected as indicated by the reference character 3l. Air is admitted through the small end of the frustrunr-shaped part 3l and circulates in the coils of a helix 33, the coils of which are mounted in the parts 3i and 32 and so adjusted therein that the outer edge of the coil engaged with the inner side walls of the parts 3! and 32. The coil is provided at its center with a conduit 34 flared at both ends in reverse directions to the members 3l and 32. The air thus circulates in this conduit 34 and in the coils of the helix 33, thereby forming a compressing and expanding device for the air before it reaches the blast pipe 1. The small end of member 32 is screw threaded for engagement with ther screw-threaded end of the blast pipe 1. The numeral 35 indicates a distributor for supplying a liquid combustion supporting agent or pulverized coal to the automatically aerated furnace.

It will appear from Figure 1 that, in use, the steam is taken from the dome 35 of the boiler furnace F through a valve 31 and passes through a pipe 38 to two branches 39 and 40. The branch 39, provided with a cock 4l and a valve 42, is connected to a pipe 43 bearing a number of ejectors 43' opening in the fire box, whereas the branch fill provided with the cock 44 and the valve 45, is connected to a pipe 45 having a plurality of ejectors 46 opening in the ashpit. Both pipes 43 and 45 are provided with pressure gauges 41 and 48 respectively.

The cylinder I6 of the dashpot is pivotally suspended from the framework of the furnace F by means of the bolt 58 and is arranged between the branch pipes 39 and 49. Also secured to the framework of the furnace F is a plurality of guide brackets 49 which have slidably mounted therein a frame 49. The piston rod 28 is secured to the frame 49 by means of the coupling 50 and the lower end of this piston rod 28 has pivotally connected thereto as at 62 a rod 82. A stop 28 is secured to the rod 82 and is adapted to engage the forked end of a lever 5l. The lower ends of this rod 82 carry the counterweights 83. The forked lever 5| is carried by a collar 5|' keyed to or in any other manner secured upon the shaft 52. Secured to the shaft 52 by means of a coupling 52 is a furnace door supporting shaft 53. The shafts 52 and 53 are journalled within suitable bearings mounted upon the framework of the furnace F and the bearings which support the furnace door shaft 53 are indicated by the letter B. The furnace door 53', when in a vertical position, closes the opening leading to the fire pot of the furnace but when the shaft 53 is rotated and this door assumes a horizontal position, the entrance to the fire pot of the furnace will be open. In order to oscillate the furnace door 53 and the shafts 52 and 53 connected thereto, I provide a handle H.

The piston 21 is normally retained in its lowermost position within the cylinder I6 by means of the counterweights 83 and when in this position, the steam cocks are closed and the furnace door 53' will also be retained in its closed position due to the connection between the piston shaft 28 and the forked lever 5l carried by the shaft 52. When this furnace door 53 is opened by using the handle H, the shaft 52, which is connected thereto will oscillate therewith in the direction of the arrow point as shown in Figure 2 of the drawings. When the shaft 52 is oscillated in this direction, the forked lever 5I will be raised and by engaging the stop 28', will cause the piston rod together with its piston, to move upwardly in the direction of the arrow point as is also shown in Figure 2 of the drawings. As the piston 21 is moved to its uppermost position within the cylinder I6, the oil will pass by the check valve contained within the piston and flow by gravity into the lower end of the cylinder, and during this upward movement of the piston, the valves 4! and 44 will be opened due to their connection to the frame 49, which latter is also fixedly connected to the piston rod 28. The oil flowing through the piston exerts a downward pressure on the obturating washer 68, which consequently descends, compressing the spring 69 and thereby uncovering the openings provided in the frustrum-shaped ring B6. The conduits 61 being no longer closed at their base allow oil to pass, this oil then entering the cylinder below the piston. Owing to the large section of the conduits 61 the passage of the oil, from above to underneath the piston, completely takes place during the time the furnace door closes, which corresponds to the end of the upward stroke of the piston and with the opening of the steam distributing cocks. During its downward movement, the piston 21, the conduits 61 of which are now closed by the washer 68. drives oil through the orice 11, the recess 1| provided about the stem 13 of the screw 14, the conduit 1I and the orifice 16 of the cylinder, above the piston. The duration of the downward stroke of the piston is controlled by varying, by means of the screw 14, the suction of passage of the oil between the needle valve 15 and the conduit 1|. It results therefrom that the admission of air land steam in the furnace can be continued during the necessary time, equivalent to that taken by the piston for effecting an entire downward stroke, its rod through the frame 49 acting at the same time on the steam cocks by progressively closing them.

It will be understood that when the furnace door is open, the lever 5I follows its movement lifting the rod 28, the frame 49, the piston 21, against the resistance oi' the oil trappedabove the piston 21; as has been explained, said o-il passes thereby through the openings of the piston and iills the space under said piston; at the same time, the piston rod 28, the frame 49 and the linksl 54 and 55 interconnecting said frame to the steam cocks 4| and 44 respectively, act to open the latter. After the furnace door has been shut, the weights 83 gradually pull the piston 21 in a downwardly direction, the oil being thereby driven above the piston and the steam cocks 4I and 44 closed.

As the use of live steam for the purpose of smoke prevention means an expense, the action of the ejectors is tol be limited to the time strictly necessary. It is understood, of course, that the time is variable according to the quality of coal, force of draught and other circumstances. The flow of oil is regulated by means of the screw 14.

Manifestly, the construction herein shown is capable of considerable modification and such modifications as come within the scope of my invention as claimed, I consider within the spirit of the invention.

I claim:

1. In a furnace smoke preventer, the combination of a bifurcated steam supply pipe, air ejectors communicating with each of the branches of said bifurcated pipe, series of sprays associated with each of said air ejectors and opening respectively in the fire box and in the ashp-it of the furnace, a pressure cylinder filled with oil, a piston sliding in said cylinder, counter weights attached tol said pistonfor normally retaining the latter in one position, vertical conduit means formed. in said cylinder, a pin screw operated from the outside for regulating the passage of oil in said conduit means, valve means in the branches of the bifurcated steam supply pipe and operatively connected to said piston, and means establishing connection between the furnace door and the piston whereby to actuate the latter directly by the movement of the doof!` against the action of said counterweights.

2. In a furnace smoke prei/enter, the combination of a bifurcated steam supply pipe, air ejectors communicating with each of the branches of said bifurcated pipe, series of sprays associated with each of said air ejectors and opening respectively in the re box Vand in the ashpit of the furnace, a pressure cylinder filled with oil, a piston sliding in said cylinder, counter weights attached to said piston, vertical conduit means formed in said cylinder, a pin screw operated from the outside for regulating the passage of oil in said conduit means, valve means in the branches of the bifurcated steam supply pipe, a frame slidably mounted adjacent said cylinder and having connections with the piston to move therewith, links attached to said frame and to said valve means, and means establishing a connection between the furnace door and the piston whereby to actuate the latter with the movement of the door.

3. In a furnace smoke preventer', the combination of a bifurcated steam supply pipe, air ejectors communicating with each of the branches of said bifurcated pipe, series of sprays associated with each of said air ejectors and opening respectively in the fire box and in the ashpit of the furnace, a pressure cylinder filled with oil, a. piston sliding in said cylinder, counter weights attached tol said piston, valve means in the branches of the bifurcated steam supply pipe and operatively connected to said piston, a frame slidably mounted adjacent said cylinder and having connections with said piston to move therewith, links attached to said frame and to said valve means, and means establishing a connection between the furnace door and the piston whereby to acutate the latter directly by the movement of the door.

RAYMOND 

